Start by staying physically active, says Gary J. Kennedy, M.D., past president of the American Association for Geriatric Psychiatry. "The rule of thumb is that a senior needs about a half hour of exercise every day," he says.

Keep it simple

That doesn't mean you have to take up jogging or head for the basketball court. Exercise can be as simple as a half-hour walk on most days of the week at a pace that lets you carry on a conversation and not get out of breath. Talk with your doctor about an exercise plan that's right for you. Then make it part of your daily routine, Dr. Kennedy says.

Even if you're living with a disability, Dr. Kennedy says, you can stay active. Try range-of-motion calisthenics, for instance.

If it's icy or frigid outside, you can work out indoors, he says. If it's not icy, you can dress warmly and head outside.

Physical activity isn't just good for your body. Research shows that regular aerobic activity -- the kind that raises your heart rate -- can reduce or prevent symptoms of depression and anxiety, says psychologist Kathy Hogan Bruen, Ph.D., senior director of prevention for the National Mental Health Association.

Dr. Kennedy suggests other ways that seniors can focus on "successful aging" in any season:

Maintain social contacts. If you can't get out much, regular phone calls are a good way to keep in touch with others.

Stay involved. That could include religious, social, or cultural events, such as prayer meetings. (Watching religious programs on television isn't the same thing, Dr. Kennedy adds.)

Focus on nutrition

Don't let winter take a bite out of your diet: Pay attention to nutrition, especially to getting enough fruits and vegetables. You can find a variety of fresh fruits and vegetables year round at the supermarket, or buy frozen fruits and vegetables to have them on hand if the weather turns bad and you can't get to the store.

Also, be sure you're getting enough calcium and vitamin D, available as supplements or in fortified, ready-to-eat cereals. Omega-3 fatty acids may help your heart health, so be sure your diet includes a little bit of fish, nuts (specifically walnuts), and soybeans, says Susan Moores, R.D., a spokeswoman for the American Dietetic Association.

If you'd like to learn more about good nutrition, sign up for a class at a local hospital or through a community education program. Have a meal with friends, says Moores. "Appetites seem to perk up when you enjoy company while you are eating."